One interesting idea could be the integration of the faction system from Divergent into Hogwarts. For example, students might be sorted not only by houses but also by factions, leading to new social dynamics and conflicts. Another idea could be characters from Divergent having magical abilities in the Harry Potter world, and how they would use those abilities in the context of the wizarding world's rules and challenges.
One idea could be that the characters from Divergent are magically transported to the wizarding world of Harry Potter. They could be sorted into Hogwarts houses based on their Divergent faction traits. For example, the Dauntless might be sorted into Gryffindor for their courage.
One interesting plot could be a crossover where characters from Harry Potter and Divergent meet in a new, magical - yet post - apocalyptic world. For example, Hermione could use her knowledge to help Tris understand the complex political and magical systems. Another idea might be a story where the sorting hat is introduced to the Divergent factions and has to sort the characters based on their personalities.
One idea could be that Merlin somehow gets transported to the Harry Potter universe. He could use his magic, which is different from the wizarding magic in Harry Potter, to solve some of the mysteries or problems there. Maybe he teams up with Harry and helps him defeat Voldemort in a unique way, like using his ancient magic knowledge.
One interesting idea could be a crossover with a fairytale world. For example, Hermione could be transported to a world like Cinderella's and meet a prince who has some magic similar to that in the Harry Potter universe. This would create a new kind of romantic dynamic where she has to balance her Hogwarts knowledge with this new, more traditional fairy - tale romance.
One idea could be that Hogwarts students discover Pokemon in the Forbidden Forest. They could start training them as part of a new magical - creature - handling class. Another idea is that a powerful Pokemon like Mewtwo ends up at Hogwarts and causes chaos among the students and teachers, who have to use their magic to deal with it. Also, a wizard could accidentally cast a spell on a Pokeball and create a new, hybrid Pokemon - magic creature.
In a Bleach and Harry Potter crossover fanfiction, it could be fascinating if the Quidditch players in Harry Potter had to face off against Hollows during a game. Imagine the chaos! Or perhaps the magic spells in Harry Potter could be used to enhance the powers of the Soul Reapers in Bleach. For example, a spell could be used to strengthen the bond between a Soul Reaper and their Zanpakuto. And if the Triwizard Tournament had a special task where the contestants had to team up with a Bleach character to defeat a powerful combined threat of a Dark wizard and a powerful Hollow.
One idea could be to have a wizard from the Harry Potter world time - travel to the Tudor era. Maybe they get mistaken for a sorcerer or a prophet. Another could be to have a Tudor character discover a hidden wizarding school in England during that time. They could then learn some basic magic and use it to their advantage in the Tudor court politics.
In a crossover, the underworld could have its own form of magic that is different from the magic in the wizarding world. Ron could be the one to first discover a connection between the two magics. He might find an old artifact in the wizarding world that has a link to the underworld. This could lead to an adventure where the trio explores the underworld to prevent a dark magic from the underworld from spreading into the wizarding world.
One idea could be to have the Gallagher family from 'Shameless' somehow end up at Hogwarts. Maybe Fiona could be mistaken for a new teacher and cause chaos in the school with her no - nonsense attitude. Another could be Lip getting involved in a magical experiment gone wrong with Hermione. He might use his street - smart knowledge to help her out in a different way than she's used to.
Perhaps the BTS members are magical creatures in the Harry Potter universe. Jin could be a Veela, with his good looks and charm that can sometimes entrance people, much like the Veela's allure in the books. Suga could be a Kneazle, independent and with a sharp mind, able to sense things others can't, just as he often has a unique perspective in his music - making. And they could all be on a quest to find a special magical object that has the power to combine the magic of their world (the BTS world) and the wizarding world of Harry Potter, and along the way, they meet Harry, Hermione, and Ron and form an unlikely alliance.